code: def test_plot_big_model(teardown, tmp_path, expand_nested):
      # Below is a very contrived big dummy model
  
      # ------- Sub-model 1
      x1_sub1 = Input(name="x1_sub1")
      x2_sub1 = Input(name="x2_sub1")
      y_t_sub1 = Input(name="y_t_sub1")
      y_p1_sub1, y_p2_sub1 = DummyMIMO()([x1_sub1, x2_sub1], y_t_sub1)
      submodel1 = Model(
          [x1_sub1, x2_sub1],
          [y_p1_sub1, y_p2_sub1],
          y_t_sub1,
          name="submodel1",
      )
  
      # ------- Sub-model 2
      y_t_sub2 = Input(name="y_t_sub2")
      y_p_sub2 = DummySISO()(y_t_sub2)
      submodel2 = Model(y_t_sub2, y_p_sub2, name="submodel2")
  
      # ------- Sub-model 3
      x1_sub3 = Input(name="x1_sub3")
      x2_sub3 = Input(name="x2_sub3")
      y_p1_sub3, y_p2_sub3 = DummyMIMO()([x1_sub3, x2_sub3])
      submodel3 = Model(
          [x1_sub3, x2_sub3], [y_p1_sub3, y_p2_sub3], name="submodel3"
      )
  
      # ------- Main model
      x = Input(name="x")
      y_t = Input(name="y_t")
      y_t_trans = submodel2(y_t)
      h1, h2 = DummySIMO()(x)
      g1, g2 = submodel3([h1, h2])
      z1, z2 = submodel1([g1, g2], y_t_trans)
      w = DummyMISO()([z1, z2])
  
      model = Model(x, w, y_t, name="main_model")
  
      filename = str(tmp_path / "test_plot_model.png")
      plot_model(
          model, filename, show=False, expand_nested=expand_nested
      )
  
file_path: baikal/tests/test_plot.py
imports: import pytest
  from baikal import Model, Input
  from baikal.plot import plot_model
  from tests.helpers.fixtures import teardown
  from tests.helpers.dummy_steps import DummyMIMO, DummySIMO, DummySISO, DummyMISO
  from tests.helpers.sklearn_steps import LogisticRegression
label_desc: Use image node_id 5 for calling a global function with example usage: test_plot_big_model(teardown, tmp_path, expand_nested) without return types